In the current design, people want the diaphragm and shutter of a camera has a light weight so that it can be carried conveniently and easily. However the prior art design do not achieve this object.
Some improvements are developed for resolving such a problem. One prior art is illustrated in FIGS. 1 and 2, in that the motor body 9 has a stator 91, a coil 92 installed on the stator 91, a rotor 93 and a driven unit 94 which is driven by the rotor 93. The rotor 93 is pivotally installed near the two ends of the stator 91. When current flows through the coil 92, two ends of the stator 91 will form as an N pole and an S pole. Thereby when the rotor 93 rotates, the diaphragm and shutter will be driven by the driving unit 94 so as to close and open or adjust the size thereof.
In the portion camera, the stator 92, coil 92 and rotor 93 of a motor body 9 are not coaxial. Referring to FIGS. 1 and 2, due to the configuration of the stator 91 of the motor body 9, it has an oblong shape. As a result, it is also heavy.
Furthermore, in the prior art configuration of the stator 91, the rotation angle of the rotor 93 is multiple of 180 degrees. It can not be adjusted in a small angle. However the shuttering time will affect the quality of image. Thus the prior art design has effect the function of the camera.
As a whole, the prior art camera diaphragm and shutter make the camera being heavy and the rotation angle is large. Thus, it is not practical.